Microsoft Outlook MCP Server
for AI Agents
Connect your AI agent to StackOne's Microsoft Outlook MCP server and give it 39 MCP tools out of the box. Auth, tool execution, and security all managed.
StackOne 
Coverage
39 Agent Actions
Create, read, update, and delete across Microsoft Outlook — and extend your agent's capabilities with custom actions.
Authentication
Agent Tool Authentication
Per-user OAuth in one call. Your Microsoft Outlook MCP server gets session-scoped tokens with zero credentials stored on your infra.
Agent Auth →
Security
Agent Protection
Every Microsoft Outlook tool response scanned for prompt injection in milliseconds — 88.7% accuracy, all running on CPU.
Prompt Injection Defense →
Performance
Max Agent Context. Min Cost.
Free up to 96% of your agent's context window to enhance reasoning and reduce cost, on every Microsoft Outlook call.
Tools Discovery →What is the Microsoft Outlook MCP Server?
A Microsoft Outlook MCP server lets AI agents read and write Microsoft Outlook data through the Model Context Protocol — Anthropic's open standard for connecting LLMs to external tools. StackOne's Microsoft Outlook MCP server ships with 39 pre-built actions, fully extensible via the Connector Builder — plus managed authentication, prompt injection defense, observability, and agent execution runtime. Connect it from MCP clients like Claude Desktop, Claude Code, Cursor, Goose, and VS Code, or from agent frameworks like OpenAI Agents SDK, LangChain, and Vercel AI SDK.
All Microsoft Outlook MCP Tools
Every action from Microsoft Outlook's API, ready for your agent. Create, read, update, and delete — scoped to exactly what you need.
Messages
- Copy Message
Copy a message to a destination folder
- List Messages
Get all messages in the signed-in user's mailbox or in a specific folder
- Get Message
Read properties and relationships of a specific message
- Update Message
Update the properties of a message object
- Move Message
Move a message to a destination folder
- Delete Message
Delete a message in the user's mailbox
Draft Messages
- Create Draft Message
Create a draft of a new message in JSON format
- Send Draft Message
Send a previously created draft message
Attachments
- Add Attachment
Add a file, item, or link attachment to a message
- List Attachments
Retrieve a list of attachments attached to a message
- Get Attachment
Get the properties and relationships of an attachment
- Delete Attachment
Delete an attachment from a message
Mail Folders
- Create Mail Folder
Create a new mail folder in the root folder
- Copy Mail Folder
Copy a mailFolder and its contents to another mailFolder
- List Mail Folders
Get the mail folder collection under the root folder
- Get Mail Folder
Retrieve properties and relationships of a mail folder
- Update Mail Folder
Update the writable properties of a mailFolder object
- Move Mail Folder
Move a mailFolder and its contents to another mailFolder
- Delete Mail Folder
Delete a mail folder
Child Folders
- Create Child Folder
Create a new child mail folder under a specified folder
- List Child Folders
Get the folder collection under the specified folder
Message Rules
- Create Message Rule
Create a message rule with conditions and actions
- List Message Rules
Get all message rules defined for the user's inbox
- Get Message Rule
Read properties and relationships of a message rule
- Update Message Rule
Change writable properties of a message rule
- Delete Message Rule
Delete a message rule
Other (13)
- Send Mail
Send a new email message using JSON or MIME format
- Create Draft Reply To Message
Create a draft to reply to the sender of a message
- Create Draft Reply All To Message
Create a draft to reply to the sender and all recipients of a message
- Create Draft To Forward Message
Create a draft to forward an existing message
- Create Message In Mail Folder
Create a new draft message in a specified mail folder
- Get Message Delta From Folder
Get a set of messages added, deleted, or updated in a specified folder
- Get Mail Folder Delta
Get incremental changes to mail folders in the mailbox
- List Folder Messages
Get all messages in a specified folder
- Forward Message
Forward a message to specified recipients
- Reply To Message
Reply to the sender of a message
- Reply All To Message
Reply to all recipients of a message
- Permanently Delete Message
Permanently delete a message and place it in the purges folder
- Permanently Delete Mail Folder
Permanently delete a mail folder and remove its items from the mailbox
Set Up Your Microsoft Outlook MCP Server in Minutes
One endpoint. Any framework. Your agent is talking to Microsoft Outlook in under 10 lines of code.
Agent Frameworks
JSON{
"mcpServers": {
"stackone": {
"command": "npx",
"args": [
"-y",
"mcp-remote@latest",
"https://api.stackone.com/mcp?x-account-id=<account_id>",
"--header",
"Authorization: Basic <YOUR_BASE64_TOKEN>"
]
}
}
}Platform Resources
MCP Code Mode: Keeping Tool Responses Out of Agent Context
Anthropic's code_execution processes data already in context. Custom MCP code mode keeps raw tool responses in a sandbox. 14K tokens vs 500.
11 min
Comparing BM25, TF-IDF, and Hybrid Search for MCP Tool Discovery
Benchmarking BM25, TF-IDF, and hybrid search for MCP tool discovery across 916 tools. The 80/20 TF-IDF/BM25 hybrid hits 21% Top-1 accuracy in under 1ms.
10 min
Indirect Prompt Injection Defense for MCP Tools: A Technical Guide
MCP tools that read emails, CRM records, and tickets are indirect prompt injection vectors. Here's how we built a two-tier defense that scans tool results in ~11ms.
12 min
MCP vs A2A: Architecture, Security, and When to Use Each
MCP vs A2A: what each protocol standardizes, how they differ, their shared security risks including indirect prompt injection, and when to use one, both, or a hybrid architecture.
12 min
MCP vs API: What 200+ Connector Builds Taught Us
MCP wraps APIs, it doesn't replace them. After building 200+ connectors that serve both, here's when each approach wins.
14 min read
Microsoft Outlook MCP Server FAQ
Does StackOne have a Microsoft Outlook MCP server?
Microsoft Outlook MCP server vs direct API integration — what's the difference?
How does Microsoft Outlook authentication work for AI agents?
origin_owner_id.Are Microsoft Outlook MCP tools vulnerable to prompt injection?
What is the context bloat of a Microsoft Outlook agent and how do I avoid it?
Can I limit which actions my Microsoft Outlook agent can access?
Can I create custom agent actions for my Microsoft Outlook MCP server?
When should I NOT use a Microsoft Outlook MCP server?
What AI frameworks and AI clients does the StackOne Microsoft Outlook MCP server support?
Put your AI agents to work
All the tools you need to build and scale AI agent integrations, with best-in-class connectivity, execution, and security.